单选题 Ms. Turner called ahead to make a reservation, but the train to Brussels was ______ fully booked.
【正确答案】 B
【答案解析】[解析] 词汇：副词
1．这是一道副词选择题，选项均为副词。
2．原文意思是“已经打了电话，但是已经预约满了”，因此空格内应填入副词already。